Storage medium for storing text-based subtitle data including style information, and reproducing apparatus and method for reproducing text-based subtitle data including style information

ABSTRACT

A storage medium for storing text-based subtitle data including style information, a reproducing apparatus and methods are provided for reproducing text-based subtitle data including style information separately recorded on the storage medium. The storage medium includes: multimedia image data; and text-based subtitle data for displaying subtitles on an image based on the multimedia image data, wherein the text-based subtitle data includes dialog information indicating subtitle contents to be displayed on the image, style information indicating an output style of the dialog information, and partial style information indicating an output style applied to a portion of the dialog information. Accordingly, subtitles can be provided in a plurality of languages without limited to the number of units of subtitle data. In addition, subtitle data can be easily produced and edited. Likewise, an output style of the subtitle data can be changed in a variety of ways. Also, a special style can be applied in order to emphasize a portion of the subtitles.

CROSS-REFERENCE TO RELATED APPLICATIONS

This application is a continuation of U.S. patent application Ser. No.11/060,595 filed on Feb. 18, 2005, now pending, which claims all benefitof Korean Patent Application No. 2004-11699, filed on Feb. 21, 2004, inthe Korean Intellectual Property Office, the disclosures of which areincorporated herein by reference.

BACKGROUND OF THE INVENTION

1. Field of the Invention

The present invention relates to reproduction of a multimedia image, andmore particularly, to a storage medium for recording text-based subtitledata including style information, and a reproducing apparatus and methodfor reproducing text-based subtitle data including style informationrecorded on the storage medium.

2. Related Art

Recently, a video stream, an audio stream, a presentation graphicsstream for providing subtitle data, and an interactive graphics streamfor providing buttons or menus to interact with a user are multiplexedin a moving picture main stream (also known as an audio-visual “AV” datastream) recorded on a storage medium for providing a high definition(HD) multimedia image having high image quality. In particular, thepresentation graphics stream for providing subtitle data also provides abitmap-based image in order to display subtitles or captions on animage.

However, bitmap-based subtitle data has a large size and is multiplexedwith other data streams. As a result, in order to guarantee a maximumbit transmission rate required by a specific application, the number ofunits of the subtitle data, which can be included in a multiplexed mainstream, is limited. In particular, when multi-lingual subtitles areprovided, problems relating to a limited number of units of subtitledata may occur.

Also, due to the bitmap-based image, production of the subtitle data andedition of the produced subtitle data are very difficult. This isbecause such subtitle data is multiplexed with other data streams suchas video, audio and interactive graphics streams. Moreover, an outputstyle of the subtitle data cannot be changed in a variety of wayseasily, that is, to change one output style into another output style ofthe subtitle data.

SUMMARY OF THE INVENTION

Aspects of the present invention advantageously provide a storage mediumin which text-based subtitle data including style information isrecorded, and a reproducing apparatus and method for reproducingtext-based subtitle data including style information recorded on such astorage medium.

According to an aspect of the present invention, a storage mediumcomprises: multimedia image data; and text-based subtitle data fordisplaying subtitles on an image based on the multimedia image data,wherein the text-based subtitle data includes dialog informationindicating subtitle contents to be displayed on the image, styleinformation indicating an output style of the dialog information, andpartial style information indicating an output style applied to aportion of the dialog information.

The dialog information may include text information regarding thesubtitle contents to be displayed on the image, and time informationregarding the time when the text information is output to a screen anddisplayed on the image.

The style information may include area information indicating a positionat which the text information is output on the image and fontinformation regarding the type, size, color, thickness, and style of anoutput font. The text-based subtitle data may include at least one unitof style sheet information that is an output style group consisting of aplurality of units of style information.

The partial style information may be output style information foremphasizing and displaying a portion of the text information, and hasrelative values with respect to the font size and/or the font colorincluded in the style information. The partial style information may beincluded in the dialog information, or stored separately from the dialoginformation in which reference information of the partial styleinformation is included.

The text-based subtitle data may also include, in addition to the styleinformation, information on whether to include predetermined styleinformation defined by a manufacturer of the storage medium.

According to another aspect of the present invention, an apparatus isprovided for reproducing multimedia image data and text-based subtitledata separately recorded on a storage medium for displaying subtitles onan image based on the multimedia image data. Such an apparatuscomprises: a buffer unit for storing style information indicating anoutput style of dialog information, which is subtitle contents to bedisplayed on the image, and partial style information indicating anoutput style applied to a portion of the dialog information; and a textsubtitle processing unit for reading the style information and thepartial style information from the buffer unit, for applying the readstyle information and partial style information to the dialoginformation, for converting the applied information to a bitmap image,and for outputting the converted bitmap image.

According to another aspect of the present invention, a method ofreproducing multimedia image data and text-based subtitle data recordedon a storage medium for displaying subtitles on an image based on themultimedia image data, comprises: reading dialog information indicatingsubtitle contents to be displayed on the image, style informationindicating an output style of the dialog information, and partial styleinformation indicating an output style applied to a portion of thedialog information; converting the dialog information to a bitmap imageto which the style and partial style are applied based on the styleinformation and the partial style information; and outputting theconverted bitmap image according to output time information included inthe dialog information.

Additional aspects and/or advantages of the invention will be set forthin part in the description which follows and, in part, will be obviousfrom the description, or may be learned by practice of the invention.

BRIEF DESCRIPTION OF THE DRAWINGS

A better understanding of the present invention will become apparentfrom the following detailed description of example embodiments and theclaims when read in connection with the accompanying drawings, allforming a part of the disclosure of this invention. While the followingwritten and illustrated disclosure focuses on disclosing exampleembodiments of the invention, it should be clearly understood that thesame is by way of illustration and example only and that the inventionis not limited thereto. The spirit and scope of the present inventionare limited only by the terms of the appended claims. The followingrepresents brief descriptions of the drawings, wherein:

FIG. 1 illustrates an example data structure of a main stream, in whicha multimedia image is encoded, and text-based subtitle data separatelyrecorded on a storage medium according to an embodiment of the presentinvention;

FIG. 2 is a block diagram of an example reproducing apparatus accordingto an embodiment of the present invention;

FIG. 3 illustrates an example data structure of text-based subtitle dataaccording to an embodiment of the present invention;

FIGS. 4A and 4B are examples of results of reproducing text-basedsubtitle data having the data structure shown in FIG. 3;

FIG. 5 illustrates a problem which can be generated when text-basedsubtitle data having the data structure shown in FIG. 3 is reproduced;

FIG. 6 illustrates an example in-line style information to beincorporated into text-based subtitle data for resolving the problemillustrated in FIG. 5 according to an embodiment of the presentinvention;

FIG. 7 illustrates an example data structure of text-based subtitle dataincorporating in-line style information according to an embodiment ofthe present invention;

FIG. 8 illustrates an example data structure of text-based subtitle datato which a reproducing apparatus can apply predetermined styleinformation according to another embodiment of the present invention;and

FIG. 9 is a flowchart illustrating a process of reproducing text-basedsubtitle data including style information according to an embodiment ofthe present invention.

DETAILED DESCRIPTION OF THE INVENTION

Hereinafter, the present invention will now be described more fully withreference to the accompanying drawings, in which example embodiments ofthe invention are shown.

FIG. 1 illustrates a data structure of a main stream 110, in which amultimedia image is encoded, and text-based subtitle data 120 separatelyrecorded from the main stream 110 on a storage medium 130, such as adigital versatile disc (DVD) according to an embodiment of the presentinvention. The main stream 110 and the text-based subtitle data 120 canbe obtained, separately or collectively, from one or more sources ordata generators.

Referring to FIG. 1, the text-based subtitle data 120 is providedseparately from the main stream 110 recorded on the storage medium 130in order to resolve problems relating to bitmap-based subtitle data. Themain stream 110, also known as an audio-visual (AV) data stream,includes a video stream 102, an audio stream 104, a presentationgraphics stream 106, and an interactive graphics stream 108, all ofwhich are multiplexed therein so as to be recorded on the storage medium130. The text-based subtitle data 120 represents data for providingsubtitles or captions of a multimedia image to be recorded on thestorage medium 130, and can be implemented using a markup language, suchas an extended markup language (XML), or using binary data. Thepresentation graphics stream 106 for providing subtitle data alsoprovides bitmap-based subtitle data in order to display subtitles (orcaptions) on a screen.

Since the text-based subtitle data 120 is recorded separately from themain stream 110, and is not multiplexed with the main stream 110, thesize of the text-based subtitle data 120 is not limited thereto.Likewise, the number of supported languages is not limited. As a result,subtitles or captions can be provided using a plurality of languages.Moreover, it is convenient to produce and edit the text-based subtitledata 120.

Turning now to FIG. 2, a block diagram of a reproducing apparatus forreproducing text-based subtitle data recorded on a storage mediumaccording to an embodiment of the present invention is illustrated. Asshown in FIG. 2, the reproducing apparatus 200, also known as a playbackdevice, comprises a presentation graphics decoder 220, which can decodeand reproduce all text-based subtitle data 120 and/or bitmap-basedsubtitle data 216, as an output, via a graphics plane 232 and a colorlook-up table (CLUT) 234.

The presentation graphics decoder 220 includes a font buffer 221 tostore font data from the text-based subtitle data 120; a coded databuffer 222 to store data from either the text-based subtitle data 120 orthe bitmap-based subtitle data 216 selected at switch 218; a switch 223;a text subtitle processor 224 to convert dialog information included inthe text-based subtitle data 120 to bitmap graphics for storage in anobject buffer 227; a stream graphics processor 225 to decode thebitmap-based subtitle data 216 and produce a bitmap image of subtitlesfor storage in the object buffer 227 and control information for storagein a composition buffer 226; and a graphics controller 228 to control anoutput of the bitmap image of the subtitles stored in the object buffer227 based on the control information stored in the composition buffer226.

In a case of the bitmap-based subtitle data 216, in the presentationgraphics decoder 220, the stream graphics processor 225 decodes thebitmap-based subtitle data and transmits a bitmap image of subtitles tothe object buffer 227 and control information of the subtitles to thecomposition buffer 226. Also, the graphics controller 228 controls anoutput of the bitmap image of the subtitles stored in the object buffer227 based on the control information stored in the composition buffer226. The output graphics image of the subtitles is formed on a graphicsplane 232 and output on a screen by applying a color with reference to acolor look-up table (CLUT) 234.

In a case of the text-based subtitle data 120, the text subtitleprocessor 224 converts dialog information of a text to bitmap graphicsby referring to font data stored in a font buffer 221 and applying styleinformation to be described later, and stores the converted bitmapgraphics in the object buffer 227. Also, the text subtitle processor 224transmits control information, such as output time information, to thecomposition buffer 226. Remaining procedures of processingbitmap-converted subtitles are the same as in the case of thebitmap-based subtitle data 216.

A detailed structure of the text-based subtitle data 120 to bereproduced will now be described with reference to an examplereproducing apparatus shown in FIG. 2. FIG. 3 illustrates a datastructure of the text-based subtitle data 120 according to an embodimentof the present invention.

Referring to FIG. 3, the text-based subtitle data 120 includes stylesheet information 310 and dialog information 320. A plurality of unitsof style sheet information 310 and/or dialog information 320 can beincluded in the text-based subtitle data 120.

For example, the style sheet information 310 includes a plurality ofunits of style information 312 indicating how to output text informationon the screen. The style information 312 includes information on anoutput style such as area information indicating an output area ofsubtitles to be displayed on the screen, position information indicatinga position of text subtitles within the output area, color informationindicating a background color, and font information for designating afont type and a font size to be applied to the text subtitles etc.

The dialog information 320 includes text information to be displayed onthe screen by being bitmap-converted, i.e., rendered, reference styleinformation to be applied when rendering the text information, andspeech (dialog) beginning and ending time information for designatingthe times when the subtitles (or captions) appear and disappear on thescreen, respectively. In particular, the dialog information 320 includesin-line style information for emphasizing a portion of the textinformation of the subtitles by applying a new style thereto. Thein-line style information preferably excludes the area information andthe position information among the style information 312 applied to anentire text, and includes the font information and color informationrequired to convert a portion of the text information to a bitmap image.

As shown in FIG. 3, the text-based subtitle data 120 comprises aplurality of units of style sheet information 310 and a plurality ofunits of dialog information 320. The style sheet information 310 is aset of the style information 312 to be applied to each of all the dialoginformation 320, and at least one unit of the style sheet information310 must exist. The manufacturer may produce additional style sheetinformation 310 so that a user can change and select a style applied tothe text information and let the additional style sheet information 310be included in the text-based subtitle data 120. The additional stylesheet information 312 to be selected by the user preferably includesonly a plurality of units of font information and color information tobe applied to the text information.

The dialog information 320 includes the text information containingsubtitle contents to be output on the screen. A plurality of units ofdialog information 320 may be included in the text-based subtitle data120 in order to process all subtitles (captions) all over an entiremultimedia image having high image quality. One unit of the dialoginformation 320 converts text information to be output on the speechbeginning time to a bitmap image by referring to the reference styleinformation and/or the in-line style information, and displays theconverted bitmap image until the speech ending time.

FIGS. 4A and 4B are examples of results of reproducing text-basedsubtitle data having the data structure shown in FIG. 3.

Referring to FIG. 4A, the text subtitle processor 224 of the reproducingapparatus 200, as shown in FIG. 2, reads style information 412, which isdirected by reference style information 422 among a plurality of unitsof style information included in style sheet information 410, selectedbased on the reference style information 422 included in dialoginformation 420 to be reproduced in operation (1). The text subtitleprocessor 224 then converts text information 424 to a bitmap image byapplying the read style information 412 to the text information 424, andoutputs the converted bitmap image. The reproducing image result 430 isshown on the right of FIG. 4A. That is, when a multimedia image isoutput, a bitmap image of text information 432 for subtitles to whichthe style information 412 directed by the reference style information422 is applied is output together for display on the screen.

FIG. 4B illustrates a reproducing image result of a case where styleinformation and in-line style information, which is applied to a portionof text information, are applied during reproduction. Referring to FIG.4B, the text subtitle processor 224 of the reproducing apparatus 200, asshown in FIG. 2, reads style information 452 directed by reference styleinformation 462 in operation (1) and applies the read style information452 to text information 464 for subtitles. Also, the text subtitleprocessor 224 reads in-line style information 466 in operation (2) andapplies the read in-line style information 466 to a portion of the textinformation 464 for subtitles. That is, when the basic style information452 included in style sheet information 450 and the in-line styleinformation 466 defined in dialog information 460 are overlapped, thein-line style information 466 is reflected on a final output anddisplayed on the screen. In this manner, the text information 464 towhich the style information 452 and the in-line style information 466are applied is converted to a bitmap image and displayed on the screen.The reproducing image result 470 is shown on the right of FIG. 4B. Abitmap image of text information 472 for subtitles output with amultimedia image together is output by applying the style information452 thereto and the in-line style information 466 to a portion thereof.

That is, when text-based subtitle data 120 is reproduced with amultimedia image having high image quality, the reproducing apparatus200, as shown, for example, in FIG. 2, selects style sheet informationto be applied in an initial reproduction of the text-based subtitle data120 among a plurality of units of style sheet information stored on astorage medium. If additional information indicating style sheetinformation to be initially applied is included in the style sheetinformation, the reproducing apparatus 200, shown in FIG. 2, can selectthe style sheet information to be applied in the initial reproduction ofthe text-based subtitle data 120 with reference to the additionalinformation. In other words, first defined style sheet information amongthe plurality of units of style sheet information can be selected. Theselected style sheet information is applied to all of dialog informationunless a style change request is generated by the user.

However, in a case where the manufacturer has produced a plurality ofunits of style sheet information and the user can select one of aplurality of styles, that is, in a case where the style change requestis generated by the user, a problem may be generated. When the stylechange request is generated by the user, new style information includedin new style sheet information is applied due to reference styleinformation included in subsequently output dialog information. However,if the newly applied style information is equal to previous in-linestyle information, no change is generated in a portion of textinformation directed by the in-line style information. As a result, theoriginal purpose that the manufacturer desired to emphasize a portion ofthe text information using the in-line style information cannot berealized. FIG. 5 illustrates a problem which can be generated whentext-based subtitle data having the data structure shown in FIG. 3 isreproduced.

Referring to FIG. 5, a process of a case where a request of changingfirst style information 512 to second style information 522 is receivedby a user is illustrated. An image 540 on the bottom-left of FIG. 5 isshown a result output by applying the first style information 512 beforethe style change request is generated. That is, a result that in-linestyle information 536 is applied to a portion of the text information534 after the first style information 512 directed by reference styleinformation 532 is applied to entire text information 534 is shown.Accordingly, the first style information 512 is applied to entiresubtitles, and the portion of the text information 534 is emphasized anddisplayed due to the in-line style information 536.

However, as shown on the bottom-right of FIG. 5, an image 550 displayedby newly applying the second style information 522 after the stylechange request is generated by the user shows that an original purposeof the manufacturer who desired to emphasize a portion of the textinformation using the in-line style information 536 is not achieved.This can be generated when the second style information 522 is equal tothe in-line style information 536.

An example in-line style information to be incorporated into text-basedsubtitle data for resolving the problem as described in connection withFIG. 5 will now be described herein below.

FIG. 6 illustrates an example in-line style information to beincorporated into text-based subtitle data for resolving the problemillustrated in FIG. 5 according to an embodiment of the presentinvention. Referring to FIG. 6, in-line style information 610 of thetext-based subtitle data 120 includes a font type, relative font sizeinformation, and relative color information. In addition, the in-linestyle information 610 may also include information such as thickness anditalics.

As described in connection with FIG. 6, since style sheet informationincludes only information on the size of the font and a color, anemphasis effect on the font type, the thickness, and the italics can bemaintained even if the style sheet information is changed to new stylesheet information by the user. However, in a case of the size of thefont and the color, the problem described in FIG. 5 can be generated.Therefore, it is preferable that the in-line style information 610includes relative font size information and relative color informationso that relative values are applied based on currently applied font sizeand color values of basic style information without using absolutevalues for attribute values of font size and color information includedin the in-line style information 610.

That is, by using relative attribute values for the font size and color,an emphasis effect due to the in-line style information 610 can bemaintained even if the style sheet information is changed by the user.Here, it is preferable that the reproducing apparatus 200, as shown, forexample, in FIG. 2, can reestablish the font size and color values to arealizable size and the minimum or maximum value of the color in a casewhere a relevant font is out of a range of the realizable size or color.

FIG. 7 illustrates an example data structure of text-based subtitle dataaccording to another embodiment of the present invention. As shown inFIG. 7, the text-based subtitle data 120 comprises a plurality of unitsof style sheet information 710 and a plurality of dialog information720.

In contrast to FIG. 3, in which the text-based subtitle data 120 isshown such that the in-line style information is included in the dialoginformation 320 separate from the style sheet information 310, thetext-based subtitle data 120 is shown in FIG. 7, such that style sheetinformation 710 includes basic style information 712 and in-line styleinformation 714 which can be applied to a portion of text information.In addition, dialog information 720 also includes reference in-linestyle information for referring to an identifier of the in-line styleinformation 714 included in the style sheet information 710 in order todirect the in-line style information 714 to be applied to textinformation of a current dialog.

The in-line style information 714 included in the style sheetinformation 710 defines a font size and a color to show an emphasiseffect based on the basic style information 712. Accordingly, even ifthe style sheet information 710 is changed by the user, by applyingin-line style information 714 separately defined by the changed stylesheet information, the manufacturer's intention to emphasize a portionof text information can advantageously be realized.

The in-line style information 714 follows an attribute of the basicstyle information 712 with respect to information on an area andposition in which the portion of the text information is displayed, andcan include font type, font size, and color information as renderinginformation to be used for emphasizing the portion of the textinformation.

As another example embodiment of the present invention, separately fromthe fact that the manufacturer defines style information to be appliedto text information, the reproducing apparatus (or playback device), asshown, for example, in FIG. 2, for reproducing text-based subtitle dataincluding style information recorded on a storage medium may set thestyle information to be applied to the text information at will. Thatis, a basic attribute follows style information included in thetext-based subtitle data described above, and a portion of the styleinformation, such as a font type, a font size, and a color, may bechanged by the reproducing apparatus. In other words, the reproducingapparatus 200, as shown, for example, in FIG. 2, may output textinformation by rendering a different output style using built-in styleinformation. Due to these functions of the reproducing apparatus 200, asshown in FIG. 2, an output format is different from a format set by themanufacturer in general.

A method for resolving this problem will now be described in detail.FIG. 8 illustrates an example data structure of text-based subtitle datato which a reproducing apparatus can apply predetermined styleinformation according to another embodiment of the present invention.

Referring to FIG. 8, in order to resolve the problem that thereproducing apparatus 200, as shown, for example, in FIG. 2, appliesstyle information to text information at will regardless of theintention of the manufacturer, the text-based subtitle data 120 furtherincludes information 830 indicating whether to permit predeterminedstyle information to be applied to the reproducing apparatus, as shown,for example, in FIG. 2. Such information 830 represents informationindicating whether the manufacturer allows the predetermined styleinformation to be applied to a reproducing apparatus 200, shown in FIG.2. When the manufacturer allows the predetermined style information tobe applied, text information can be output by applying the predeterminedstyle information supported by the reproducing apparatus 200, shown inFIG. 2.

Using the information 830 indicating whether to permit the predeterminedstyle information supported by the reproducing apparatus 200, shown inFIG. 2, the predetermined style information to be applied to all ofstyle information included in the text-based subtitle data 120 can bedetermined by storing the information 830 separately from style sheetinformation 810 as shown in operation (1) of FIG. 8. Also, whether topermit the predetermined style information to be applied to onlyspecific style information can be determined by storing the information830 for each unit of the style sheet information 810 as shown inoperation (2) of FIG. 8.

A method of reproducing text-based subtitle data including styleinformation will now be described based on an example data structure oftext-based subtitle data recorded on a storage medium and an examplereproducing apparatus, shown in FIG. 2. FIG. 9 is a flowchartillustrating a process of reproducing text-based subtitle data includingstyle information according to an embodiment of the present invention.

Referring to FIG. 9, text-based subtitle data 120 including dialoginformation, style sheet information, and in-line style information, asshown, for example, in FIG. 3, or FIG. 7, is read from a storage mediumin operation 910. In operation 920, style information is applied to asubtitle text included in the dialog information, the in-line styleinformation is applied to a portion of the subtitle text, and thesubtitle text is converted to a bitmap image. The converted bitmap imageis output based on time information on which a speech (or caption) isoutput to a screen for a visual display, in operation 930.

As described from the foregoing, the present invention advantageouslyprovides a storage medium, in which text-based subtitle data including aplurality of units of style information is recorded, and a reproducingapparatus and method therefor, such that subtitles can be provided in aplurality of languages without being limited to the number of units ofsubtitle data. As a result, subtitle data can be easily produced andedited, and an output style of the subtitle data can be changed in avariety of ways. Moreover, a special style can be applied in order toemphasize a portion of the subtitles.

Example embodiments of the present invention can also be written ascomputer programs and can be implemented in general-use digitalcomputers that execute the programs using a computer readable medium.Examples of the computer readable medium include magnetic storage media(e.g., ROM, floppy disks, hard disks, etc.), and optical recording media(e.g., CD-ROMs, DVDs, etc.). The program stored on a computer readablemedium can also be distributed over network coupled computer systems sothat the computer readable code is stored and executed in a distributedfashion.

While there have been illustrated and described what are considered tobe example embodiments of the present invention, it will be understoodby those skilled in the art and as technology develops that variouschanges and modification may be made, and equivalents may be substitutedfor elements thereof without departing from the spirit and scope of thepresent invention. Many modifications may be made to adapt the teachingsof the present invention to a particular situation without departingfrom the scope thereof. For example, many computer readable media ordata storage devices may be utilized, as long as reference signals arerecorded thereon to reflect optimum recording conditions. In addition,text-based subtitle data can also be configured differently as shown inFIG. 3 or FIG. 7. Similarly, the CPU can be implemented as a chipsethaving firmware, or alternatively, a general or special purposedcomputer programmed to perform the methods as described with referenceto FIG. 2 and FIG. 9. Accordingly, it is intended, therefore, that thepresent invention not be limited to the various example embodimentsdisclosed, but that the present invention includes all embodimentsfalling within the scope of the appended claims.

1. A method of reproducing multimedia image data and text-based subtitledata recorded on a computer readable storage medium for displayingsubtitles on an image based on the multimedia image data, the methodcomprising: reading text-based subtitle data including dialoginformation and style set, the dialog information comprising textinformation, reference style information and partial style information,and the style set comprising a plurality of style information; andapplying one style information of the plurality of style information tothe text information, using the reference style information indicatingone style information which is to be applied to the text informationamong the plurality of style information, and applying the partial styleinformation to a portion of the text information.
 2. The method asclaimed in claim 1, wherein the style information includes areainformation indicating a position at which the text information isdisplayed and font information regarding a size and a color of a font ofthe text information.
 3. The method as claimed in claim 1, wherein thedialog information includes information indicating the time when thetext information is output and the time when the output of the textinformation is finished.